Abstract:
Power quality is one of major concern in modern
era and has become important with the introduction of very
advanced devices, whose performance is very sensitive to
the quality of powe r supply. Power quality problem such as
non standard voltage, current or frequency leads to
equipment failures of end user. The major power quality
problems are voltage sag, swell and harmonics. To solve
this problem, custom power device called Dynamic Vo ltage
Restorer (DVR), which is the most efficient and effective
modern device used in the power distribution networks.
The objective of the proposed DVR is to compensate the
voltage sag, swell and harmonics by load side
compensation. To compensate the vol tage distortions for
long duration, DVR without energy storage and load side
connected shunt converter topology is proposed. Based on
this topology, the DVR consists of uncontrolled rectifier for
giving DC supply to Z Source converter through DC link.
Z Source Converter based topology is used in order to
enhance the voltage restoration property of the device.
The control
of shoot through capability of Z Source
Inverter using IGBTs provide s ride through capability
during voltage sag and swell , which incre ases its reliability.
A control scheme called Hysteresis Voltage loop controller
is proposed to synthesis the desired injecting voltage.
Simulation and experimental results are provided to
demonstrate the validity and the features of the proposed
novel met hod.